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Systematic Enso-Driven Nutrient Variability Recorded By Central Equatorial Pacific Corals, Michele Lavigne, Intan S. Nurhati, Kim M. Cobb, Helen V. Mcgregor, Daniel Sinclair, Robert M. Sherrell
Systematic Enso-Driven Nutrient Variability Recorded By Central Equatorial Pacific Corals, Michele Lavigne, Intan S. Nurhati, Kim M. Cobb, Helen V. Mcgregor, Daniel Sinclair, Robert M. Sherrell
Faculty of Science, Medicine and Health - Papers: part A
[1] Variations in ocean productivity are driven largely by nutrient supply to the photic zone, but temporal records of nutrient variability are sparse. Here we show scleractinian coral P/Ca proxy records of variations in phosphate concentrations during El Niño Southern Oscillation (ENSO) cycles in the central equatorial Pacific. Covarying P/Ca records in Porites corals from Christmas and Fanning Islands show a regional ~40% decrease during the upwelling relaxation of the 1997–1998 El Niño, consistent with less frequent nutrient measurements from this area. Similar ~35–45% skeletal P/Ca decreases occur during the 1982–1983 and 1986–1987 El Niño events, which predate satellite color …
Rates Of Shoreline Change Along The Coast Of Bangladesh, Md. Golam Mahabub Sarwar, Colin D. Woodroffe
Rates Of Shoreline Change Along The Coast Of Bangladesh, Md. Golam Mahabub Sarwar, Colin D. Woodroffe
Faculty of Science, Medicine and Health - Papers: part A
Bangladesh, at the confluence of the sediment-laden Ganges and Brahmaputra Rivers, supports an enormous and rapidly growing population (>140 million in 2011), across low-lying alluvial and delta plains that have accumulated over the past few thousand years. It has been identified as one of the most vulnerable places in the world to the impacts of climate change and sea-level rise. Although abundant sediment supply has resulted in accretion on some parts of the coast of Bangladesh, others are experiencing rapid erosion. We report a systematic assessment of rates of shoreline change over a 20-year period from 1989 to 2009, …
Uv Photodissociation Action Spectroscopy Of Haloanilinium Ions In A Linear Quadrupole Ion Trap Mass Spectrometer, Christopher S. Hansen, Benjamin B. Kirk, Stephen J. Blanksby, Richard A. J O'Hair, Adam J. Trevitt
Uv Photodissociation Action Spectroscopy Of Haloanilinium Ions In A Linear Quadrupole Ion Trap Mass Spectrometer, Christopher S. Hansen, Benjamin B. Kirk, Stephen J. Blanksby, Richard A. J O'Hair, Adam J. Trevitt
Faculty of Science, Medicine and Health - Papers: part A
UV-vis photodissociation action spectroscopy is becoming increasingly prevalent because of advances in, and commercial availability of, ion trapping technologies and tunable laser sources. This study outlines in detail an instrumental arrangement, combining a commercial ion-trap mass spectrometer and tunable nanosecond pulsed laser source, for performing fully automated photodissociation action spectroscopy on gas-phase ions. The components of the instrumentation are outlined, including the optical and electronic interfacing, in addition to the control software for automating the experiment and performing online analysis of the spectra. To demonstrate the utility of this ensemble, the photodissociation action spectra of 4-chloroanilinium, 4-bromoanilinium, and 4-iodoanilinium cations …
Effects Of Atmospheric Light Scattering On Spectroscopic Observations Of Greenhouse Gases From Space. Part 2: Algorithm Intercomparison In The Gosat Data Processing For Co2 Retrievals Over Tccon Sites, Sergey Oshchepkov, Andrey Bril, Tatsuya Yokota, Paul O. Wennberg, Nicholas M. Deutscher, Debra Wunch, Geoffrey C. Toon, Yukio Yoshida, Christopher W. O'Dell, David Crisp, Charles E. Miller, Christian Frankenberg, Andre Butz, Ilse Aben, Sandrine Guerlet, Otto Hasekamp, Hartmut Boesch, Austin Cogan, Robert Parker, David Griffith, Ronald Macatangay, Justus Notholt, Ralf Sussmann, Markus Rettinger, Vanessa Sherlock, John Robinson, Esko Kyro, Pauli Heikkinen, Dietrich G. Feist, Isamu Morino, Nikolay Kadygrov, Dmitry Belikov, Shamil Maksyutov, Tsuneo Matsunaga, Osamu Uchino, Hiroshi Watanabe
Effects Of Atmospheric Light Scattering On Spectroscopic Observations Of Greenhouse Gases From Space. Part 2: Algorithm Intercomparison In The Gosat Data Processing For Co2 Retrievals Over Tccon Sites, Sergey Oshchepkov, Andrey Bril, Tatsuya Yokota, Paul O. Wennberg, Nicholas M. Deutscher, Debra Wunch, Geoffrey C. Toon, Yukio Yoshida, Christopher W. O'Dell, David Crisp, Charles E. Miller, Christian Frankenberg, Andre Butz, Ilse Aben, Sandrine Guerlet, Otto Hasekamp, Hartmut Boesch, Austin Cogan, Robert Parker, David Griffith, Ronald Macatangay, Justus Notholt, Ralf Sussmann, Markus Rettinger, Vanessa Sherlock, John Robinson, Esko Kyro, Pauli Heikkinen, Dietrich G. Feist, Isamu Morino, Nikolay Kadygrov, Dmitry Belikov, Shamil Maksyutov, Tsuneo Matsunaga, Osamu Uchino, Hiroshi Watanabe
Faculty of Science, Medicine and Health - Papers: part A
This report is the second in a series of companion papers describing the effects of atmospheric light scattering in observations of atmospheric carbon dioxide (CO2) by the Greenhouse gases Observing SATellite (GOSAT), in orbit since 23 January 2009. Here we summarize the retrievals from six previously published algorithms; retrieving column-averaged dry air mole fractions of CO2 (XCO2) during 22 months of operation of GOSAT from June 2009. First, we compare data products from each algorithm with ground-based remote sensing observations by Total Carbon Column Observing Network (TCCON). Our GOSAT-TCCON coincidence criteria select satellite observations within a 5° radius of 11 …
Mid-Holocene Age Obtained For Nested Diamond Pattern Petroglyph In The Billasurgam Cave Complex, Kurnool District, Southern India, Paul S.C Tacon, Nicole Boivin, Michael Petraglia, James Blinkhorn, Allan Chivas, Richard G. Roberts, David Fink, Thomas Higham, Peter Ditchfield, Ravi Korisettar, Jian-Xin Zhao
Mid-Holocene Age Obtained For Nested Diamond Pattern Petroglyph In The Billasurgam Cave Complex, Kurnool District, Southern India, Paul S.C Tacon, Nicole Boivin, Michael Petraglia, James Blinkhorn, Allan Chivas, Richard G. Roberts, David Fink, Thomas Higham, Peter Ditchfield, Ravi Korisettar, Jian-Xin Zhao
Faculty of Science, Medicine and Health - Papers: part A
India has one of the world's largest and most significant bodies of rock paintings and engravings, yet not a single rock art site or image has been directly and accurately dated using radiometric techniques. Here we report on results from the Billasurgam Cave complex near Kurnool in southern India. Although this cave complex has been investigated archaeologically since the late 1800s, it was not until 2008 that a large petroglyph, consisting of the remains of three nested diamond designs on a stalactite, was noted. In order to determine if this petroglyph had been made recently, flowstone was sampled from on …
N-Nitrosamine Rejection By Nanofiltration And Reverse Osmosis Membranes: The Importance Of Membrane Characteristics, Takahiro Fujioka, Stuart J. Khan, James A. Mcdonald, Annalie Roux, Yvan Poussade, Jorg E. Drewes, Long D. Nghiem
N-Nitrosamine Rejection By Nanofiltration And Reverse Osmosis Membranes: The Importance Of Membrane Characteristics, Takahiro Fujioka, Stuart J. Khan, James A. Mcdonald, Annalie Roux, Yvan Poussade, Jorg E. Drewes, Long D. Nghiem
Faculty of Science, Medicine and Health - Papers: part A
The influence of membrane characteristics on the rejection of eight N-nitrosamines was investigated using one nanofiltration (NF), one seawater reverse osmosis (SWRO) and six low pressure reverse osmosis (LPRO) membranes. The rejection of the two lowest molecular weight N-nitrosamines, namely N-nitrosodimethylamine (NDMA) and N-nitrosomethylethylamine (NMEA), varied in the range from 8-82% to 23-94%, respectively. In general, the rejection of NDMA and NMEA increased with decreasing membrane permeability. The impact of membrane characteristics became less important for higher molecular weight N-nitrosamines. Among the four LPRO membranes (i.e. ESPA2, LFC3, TFC-HR and 70LW) that are commonly used for water reclamation applications, similar …
Coastal Evolution On Volcanic Oceanic Islands: A Complex Interplay Between Volcanism, Erosion, Sedimentation, Sea-Level Change And Biogenic Production, Ricardo S. Ramalho, Rui Quartau, Alan S. Trenhaile, Neil C. Mitchell, Colin D. Woodroffe, Sergio P. Avila
Coastal Evolution On Volcanic Oceanic Islands: A Complex Interplay Between Volcanism, Erosion, Sedimentation, Sea-Level Change And Biogenic Production, Ricardo S. Ramalho, Rui Quartau, Alan S. Trenhaile, Neil C. Mitchell, Colin D. Woodroffe, Sergio P. Avila
Faculty of Science, Medicine and Health - Papers: part A
The growth and decay of oceanic hotspot volcanoes are intrinsically related to a competition between volcanic construction and erosive destruction, and coastlines are at the forefront of such confrontation. In this paper, we review the several mechanisms that interact and contribute to the development of coastlines on oceanic island volcanoes, and how these processes evolve throughout the islands' lifetime. Volcanic constructional processes dominate during the emergent island and subaerial shield-building stages. During the emergent island stage, surtseyan activity prevails and hydroclastic and pyroclastic structures form; these structures are generally ephemeral because they can be rapidly obliterated by marine erosion. With …
Protoliths Of Enigmatic Archaean Gneisses Established From Zircon Inclusion Studies: Case Study Of The Caozhuang Quartzite, E. Hebei, China, Allen Phillip Nutman, Ronni Maciejowski, Yusheng Wan
Protoliths Of Enigmatic Archaean Gneisses Established From Zircon Inclusion Studies: Case Study Of The Caozhuang Quartzite, E. Hebei, China, Allen Phillip Nutman, Ronni Maciejowski, Yusheng Wan
Faculty of Science, Medicine and Health - Papers: part A
A diverse suite of Archaean gneisses at Huangbaiyu village in the North China Craton, includes rare fuchsite-bearing (Cr-muscovite) siliceous rocks - known as the Caozhuang quartzite. The Caozhuang quartzite is strongly deformed and locally mylonitic, with silica penetration and pegmatite veining common. It contains abundant 3880-3600 Ma and some Palaeoarchaean zircons. Because of its siliceous nature, the presence of fuchsite and its complex zircon age distribution, it has until now been accepted as a (mature) quartzite. However, the Caozhuang quartzite sample studied here is feldspathic. The shape and cathodoluminescence petrography of the Caozhuang quartzite zircons show they resemble those found …
Assessing Processes And Timescales Of Sandstone Landscape Formation In Zhangjiajie Geopark Of China, H Huang, Jan-Hendrik May, David Fink, Toshiyuki Fujioka, Robert Wray, J Gu
Assessing Processes And Timescales Of Sandstone Landscape Formation In Zhangjiajie Geopark Of China, H Huang, Jan-Hendrik May, David Fink, Toshiyuki Fujioka, Robert Wray, J Gu
Faculty of Science, Medicine and Health - Papers: part A
No abstract provided.
A Raised Ois 3 Sea Level Recorded In Coastal Sediments, Southern Changjiang Delta Plain, China, Zhanghua Wang, Brian G. Jones, Ting Chen, Baocheng Zhao, Qing Zhan
A Raised Ois 3 Sea Level Recorded In Coastal Sediments, Southern Changjiang Delta Plain, China, Zhanghua Wang, Brian G. Jones, Ting Chen, Baocheng Zhao, Qing Zhan
Faculty of Science, Medicine and Health - Papers: part A
The distribution of marine-influenced oxygen isotope stage (OIS) 5 to OIS 1 sediments was examined in several late Quaternary boreholes from the southern Changjiang (Yangtze) delta plain, China, using different dating methods including OSL, U-series, AMS 14C and paleomagnetism. Results demonstrate that coastal and estuarine deposition during OIS 5 and OIS 3 occurred throughout the study area. However, Holocene transgressive sediments were absent on the Taihu block. The burial depth of intertidal to subtidal sediment deposited during OIS 5e records 30-80 m subsidence caused by sediment compaction and tectonic movement since that time. However, coastal sediments formed during the late …
First Occurrence And Biogeographical Significance Of The Operculate Tetracoral Goniophyllum From The Wenlock (Silurian) Of Baillie-Hamilton Island, Canadian Arctic, Anthony J. Wright
First Occurrence And Biogeographical Significance Of The Operculate Tetracoral Goniophyllum From The Wenlock (Silurian) Of Baillie-Hamilton Island, Canadian Arctic, Anthony J. Wright
Faculty of Science, Medicine and Health - Papers: part A
Opercula of the Silurian tetracoral genera Goniophyllum and Rhizophyllum are described from early Wenlock (Sheinwoodian) strata of the Cape Phillips Formation, Baillie-Hamilton Island, Canadian Arctic. This is the first record of Goniophyllum in northern Laurentia, emphasising previously recognised faunal connections of this region with Baltica and Avalonia. As the opercula of Goniophyllum belong mostly to very early juveniles, which have not previously been documented, specific identification is impossible.
Characterisation Of The Ionic Products Arising From Electron Photodetachment Of Simple Dicarboxylate Dianions, Benjamin B. Kirk, Adam J. Trevitt, Berwyck L. Poad, Stephen J. Blanksby
Characterisation Of The Ionic Products Arising From Electron Photodetachment Of Simple Dicarboxylate Dianions, Benjamin B. Kirk, Adam J. Trevitt, Berwyck L. Poad, Stephen J. Blanksby
Faculty of Science, Medicine and Health - Papers: part A
Much of what we currently understand about the structure and energetics of multiply charged anions in the gas phase is derived from the measurement of photoelectron spectra of simple dicarboxylate dianions. Here we have employed a modified linear ion-trap mass spectrometer to undertake complementary investigations of the ionic products resulting from laser-initiated electron photodetachment of two model dianions. Electron photodetachment (ePD) of the [M-2H]2- dianions formed from glutaric and adipic acid were found to result in a significant loss of ion signal overall, which is consistent with photoelectron studies that report the emission of slow secondary electrons (Xing et al., …
Hydroxyl Radical Formation In The Gas Phase Oxidation Of Distonic 2-Methylphenyl Radical Cations, Matthew Prendergast, Phillip A. Cooper, Benjamin B. Kirk, Gabriel Da Silva, Stephen J. Blanksby, Adam J. Trevitt
Hydroxyl Radical Formation In The Gas Phase Oxidation Of Distonic 2-Methylphenyl Radical Cations, Matthew Prendergast, Phillip A. Cooper, Benjamin B. Kirk, Gabriel Da Silva, Stephen J. Blanksby, Adam J. Trevitt
Faculty of Science, Medicine and Health - Papers: part A
The reactions of distonic 4-(N,N,N-trimethylammonium)-2-methylphenyl and 5-(N,N,N-trimethylammonium)-2-methylphenyl radical cations (m/z 149) with O 2 are studied in the gas phase using ion-trap mass spectrometry. Photodissociation (PD) of halogenated precursors gives rise to the target distonic charge-tagged methylphenyl radical whereas collision-induced dissociation (CID) is found to produce unreactive radical ions. The PD generated distonic radicals, however, react rapidly with O2 to form [M + O2]•+ and [M + O2 - OH]•+ ions, detected at m/z 181 and m/z 164, respectively. Quantum chemical calculations using G3SX(MP3) and M06-2X theories are deployed to examine key decomposition pathways of the 5-(N,N,N-trimethylammonium)-2-methylphenylperoxyl radical and rationalise …
The Tectonic Evolution Of A Neo-Tethyan (Eocene-Oligocene) Island-Arc (Walash And Naopurdan Groups) In The Kurdistan Region Of The Northeast Iraqi Zagros Suture Zone, Sarmad A. Ali, Solomon Buckman, K J. Aswad, Brian G. Jones, Sabah A. Ismail, Allen P. Nutman
The Tectonic Evolution Of A Neo-Tethyan (Eocene-Oligocene) Island-Arc (Walash And Naopurdan Groups) In The Kurdistan Region Of The Northeast Iraqi Zagros Suture Zone, Sarmad A. Ali, Solomon Buckman, K J. Aswad, Brian G. Jones, Sabah A. Ismail, Allen P. Nutman
Faculty of Science, Medicine and Health - Papers: part A
The Walash and Naopurdan groups are incorporated into the lower allochthonous thrust sheet in the Iraqi Zagros Suture Zone (IZSZ). 40Ar–39Ar dates on magmatic feldspar separates from both Walash and Naopurdan volcanic rocks indicate an Eocene–Oligocene age (43.01 ± 0.15 to 24.31 ± 0.60 Ma). The Walash and Naopurdan groups form a thrust sheet that is structurally overlain by an upper allochthon of Cretaceous arc-related rocks (106–92 Ma) now known as the Hasanbag igneous complex (formerly known as the Gemo–Qandil Group). The Walash and Naopurdan lower allochthon is thrust over the foreland basin Red Beds series. Volcanic and subvolcanic units …
Simultaneous Retrieval Of Atmospheric Co2 And Light Path Modification From Space-Based Spectroscopic Observations Of Greenhouse Gases: Methodology And Application To Gosat Measurements Over Tccon Sites, Sergey Oshchepkov, Andrey Bril, Tatsuya Yokota, Yukio Yoshida, Thomas Blumenstock, Nicholas M. Deutscher, Susanne Dohe, Ronald Macatangay, Isamu Morino, Justus Notholt, Markus Rettinger, Christof Petri, Matthias Schneider, Ralf Sussmann, Osamu Uchino, Voltaire A. Velazco, Debra Wunch, Dmitry Belikov
Simultaneous Retrieval Of Atmospheric Co2 And Light Path Modification From Space-Based Spectroscopic Observations Of Greenhouse Gases: Methodology And Application To Gosat Measurements Over Tccon Sites, Sergey Oshchepkov, Andrey Bril, Tatsuya Yokota, Yukio Yoshida, Thomas Blumenstock, Nicholas M. Deutscher, Susanne Dohe, Ronald Macatangay, Isamu Morino, Justus Notholt, Markus Rettinger, Christof Petri, Matthias Schneider, Ralf Sussmann, Osamu Uchino, Voltaire A. Velazco, Debra Wunch, Dmitry Belikov
Faculty of Science, Medicine and Health - Papers: part A
This paper presents an improved photon path length probability density function method that permits simultaneous retrievals of column-average greenhouse gas mole fractions and light path modifications through the atmosphere when processing high-resolution radiance spectra acquired from space. We primarily describe the methodology and retrieval setup and then apply them to the processing of spectra measured by the Greenhouse gases Observing SATellite (GOSAT). We have demonstrated substantial improvements of the data processing with simultaneous carbon dioxide and light path retrievals and reasonable agreement of the satellite-based retrievals against ground-based Fourier transform spectrometer measurements provided by the Total Carbon Column Observing Network …
Formation Of Dimethylketene And Methacrolein By Reaction Of The Ch Radical With Acetone, Fabien Goulay, Adeeb Derakhshan, Eamonn Maher, Adam J. Trevitt, John D. Savee, Adam M. Scheer, David L. Osborn, Craig A. Taatjes
Formation Of Dimethylketene And Methacrolein By Reaction Of The Ch Radical With Acetone, Fabien Goulay, Adeeb Derakhshan, Eamonn Maher, Adam J. Trevitt, John D. Savee, Adam M. Scheer, David L. Osborn, Craig A. Taatjes
Faculty of Science, Medicine and Health - Papers: part A
The reaction of the methylidyne radical (CH) with acetone ((CH3)2CO) is studied at room temperature and at a pressure of 4 Torr (533.3 Pa) using a multiplexed photoionization mass spectrometer coupled to the tunable vacuum ultraviolet synchrotron radiation of the Advanced Light Source at Lawrence Berkeley National Laboratory. The CH radicals are generated by 248 nm multiphoton photolysis of bromoform and react with acetone in an excess of helium and nitrogen gas flow. The main observed reaction exit channel is elimination of a hydrogen atom to form C4H6O isomers. Analysis of photoionization spectra identifies dimethylketene and methacrolein as the only …
Morphological Characterisation Of Reef Types In Torres Strait And An Assessment Of Their Carbonate Production, Javier X. Leon, Colin D. Woodroffe
Morphological Characterisation Of Reef Types In Torres Strait And An Assessment Of Their Carbonate Production, Javier X. Leon, Colin D. Woodroffe
Faculty of Science, Medicine and Health - Papers: part A
Coral reefs represent major accumulations of calcium carbonate (CaCO3). The particularly labyrinthine network of reefs in Torres Strait, north of the Great Barrier Reef (GBR), has been examined in order to estimate their gross CaCO3 productivity. The approach involved a two-step procedure, first characterising and classifying the morphology of reefs based on a classification scheme widely employed on the GBR and then estimating gross CaCO3 productivity rates across the region using a regional census-based approach. This was undertaken by independently verifying published rates of coral reef community gross production for use in Torres Strait, based on site-specific ecological and morphological …
Using Formative Feedback To Identify And Support First Year Chemistry Students With Missing Or Misconceptions. A Practice Report, Gwen Lawrie, Anthony Wright, Madeleine Schultz, Timothy Dargaville, Glennys O'Brien, Simon B. Bedford, Mark Williams, Roy Tasker, Hayden Dickson, Christopher Thompson
Using Formative Feedback To Identify And Support First Year Chemistry Students With Missing Or Misconceptions. A Practice Report, Gwen Lawrie, Anthony Wright, Madeleine Schultz, Timothy Dargaville, Glennys O'Brien, Simon B. Bedford, Mark Williams, Roy Tasker, Hayden Dickson, Christopher Thompson
Faculty of Science, Medicine and Health - Papers: part A
Students entering tertiary studies possess a diverse range of prior experiences in their academic preparation for tertiary chemistry so academics need tools to enable them to respond to issues in diversity in conceptual models possessed by entering students. Concept inventories can be used to provide formative feedback to help students identify concepts that they need to address to improve construction of subsequent understanding enabling their learning. Modular, formative learning activities that can be administered inside or outside of class in first year chemistry courses have been developed. These activities address key missing and mis-conceptions possessed by incoming student. Engagement in …
Strong Rocks Sustain Ancient Postorogenic Topography In Southern Africa, Taryn E. Scharf, Alexandru T. Codilean, Maarten De Wit, John D. Jansen, Peter W. Kubik
Strong Rocks Sustain Ancient Postorogenic Topography In Southern Africa, Taryn E. Scharf, Alexandru T. Codilean, Maarten De Wit, John D. Jansen, Peter W. Kubik
Faculty of Science, Medicine and Health - Papers: part A
The Cape Mountains of southern Africa exhibit an alpine-like topography in conjunction with some of the lowest denudation rates in the world. This presents an exception to the often-cited coupling of topography and denudation rates and suggests that steep slopes alone are not sufficient to incite the high denudation rates with which they are commonly associated. Within the Cape Mountains, slope angles are often in excess of 30° and relief frequently exceeds 1 km, yet 10Be-based catchment-averaged denudation rates vary between 2.32 ± 0.29 m/m.y. and 7.95 ± 0.90 m/m.y. We attribute the maintenance of rugged topography and suppression of …
A Methodology For The Rapid Assessment Of The Potential Impact And Hazard Of Coal Seam Gas Mining On Aquifers And The Environment, John M. Bradd, Emma Kiekebosch-Fitt, Tim J. Cohen, Sam K. Marx, Solomon Buckman
A Methodology For The Rapid Assessment Of The Potential Impact And Hazard Of Coal Seam Gas Mining On Aquifers And The Environment, John M. Bradd, Emma Kiekebosch-Fitt, Tim J. Cohen, Sam K. Marx, Solomon Buckman
Faculty of Science, Medicine and Health - Papers: part A
The potential environmental impacts and hazards of coal seam gas mining in Australia are highly contentious and poorly understood. Concerns have been raised by communities, and the Australian government has incorporated management tools and strategies to address these concerns. The primary environmental issue associated with coal seam gas mining would be on the aquifers above the target coal seam. If the upper aquifers are affected in terms of quantity and quality, then there are cumulative impacts to the surface environment such as groundwater dependent ecosystems and surface waters. This paper will examine the Australian situation with regard to coal seam …
Ultraviolet Action Spectroscopy Of Iodine Labeled Peptides And Proteins In The Gas Phase, Benjamin B. Kirk, Adam J. Trevitt, Stephen J. Blanksby, Yuanqi Tao, Benjamin N. Moore, Ryan Julian
Ultraviolet Action Spectroscopy Of Iodine Labeled Peptides And Proteins In The Gas Phase, Benjamin B. Kirk, Adam J. Trevitt, Stephen J. Blanksby, Yuanqi Tao, Benjamin N. Moore, Ryan Julian
Faculty of Science, Medicine and Health - Papers: part A
Structural investigations of large biomolecules in the gas phase are challenging. Herein, it is reported that action spectroscopy taking advantage of facile carbon-iodine bond dissociation can be used to examine the structures of large molecules, including whole proteins. Iodotyrosine serves as the active chromophore, which yields distinctive spectra depending on the solvation of the side chain by the remainder of the molecule. Isolation of the chromophore yields a double featured peak at 290 nm, which becomes a single peak with increasing solvation. Deprotonation of the side chain also leads to reduced apparent intensity and broadening of the action spectrum. The …
Rapid Differentiation Of Isomeric Lipids By Photodissociation Mass Spectrometry Of Fatty Acid Derivatives, Huong T. Pham, Adam J. Trevitt, Todd W. Mitchell, Stephen J. Blanksby
Rapid Differentiation Of Isomeric Lipids By Photodissociation Mass Spectrometry Of Fatty Acid Derivatives, Huong T. Pham, Adam J. Trevitt, Todd W. Mitchell, Stephen J. Blanksby
Faculty of Science, Medicine and Health - Papers: part A
RATIONALE Both traditional electron ionization and electrospray ionization tandem mass spectrometry have demonstrated limitations in the unambiguous identification of fatty acids. In the former case, high electron energies lead to extensive dissociation of the radical cations from which little specific structural information can be obtained. In the latter, conventional collision-induced dissociation (CID) of even-electron ions provides little intra-chain fragmentation and thus few structural diagnostics. New approaches that harness the desirable features of both methods, namely radical-driven dissociation with discrete energy deposition, are thus required.
METHODS Herein we describe the derivatization of a structurally diverse suite of fatty acids as 4-iodobenzyl …
Does Addition Of No2 To Carbon-Centered Radicals Yield Rono Or Rno2? An Investigation Using Distonic Radical Ions, Benjamin B. Kirk, Adam J. Trevitt, Stephen J. Blanksby
Does Addition Of No2 To Carbon-Centered Radicals Yield Rono Or Rno2? An Investigation Using Distonic Radical Ions, Benjamin B. Kirk, Adam J. Trevitt, Stephen J. Blanksby
Faculty of Science, Medicine and Health - Papers: part A
Nitrogen dioxide is used as a "radical scavenger" to probe the position of carbon-centered radicals within complex radical ions in the gas phase. As with analogous neutral radical reactions, this addition results in formation of an [M + NO2](+) adduct, but the structural identity of this species remains ambiguous. Specifically, the question remains: do such adducts have a nitro-(RNO2) or nitrosoxy-(RONO) moiety, or are both isomers present in the adduct population? In order to elucidate the products of such reactions, we have prepared and isolated three distonic phenyl radical cations and observed their reactions with nitrogen dioxide in the gas …
Quaternary, Gilbert Price, Dionisio Cendon, Allan Chivas, Adriana Garcia, John S. Jell
Quaternary, Gilbert Price, Dionisio Cendon, Allan Chivas, Adriana Garcia, John S. Jell
Faculty of Science, Medicine and Health - Papers: part A
Despite their limited economic utility, Queensland's Quaternary deposits have attracted considerable attention. This is because studies of these deposits could shed light on processes and mechanisms of past periods of climate change, and therefore are particularly pertinent in contemporary debates on human impacts, future climate change and environmental fluctuation.
Sandstone Versus Conglomerate Erosional Landscapes - Why Similarities? Why Differences?, Piotr Migon, Robert Wray
Sandstone Versus Conglomerate Erosional Landscapes - Why Similarities? Why Differences?, Piotr Migon, Robert Wray
Faculty of Science, Medicine and Health - Papers: part A
Abstract of oral presentation that was presented at the 8th International conference (AIG) on Geomorphology, 27-31 August 2013, Paris.
Laboratory Simulation Of Karst On Titan, Michael J. Malaska, Robert P. Hodyss, Karl L. Mitchell, Robert Wray
Laboratory Simulation Of Karst On Titan, Michael J. Malaska, Robert P. Hodyss, Karl L. Mitchell, Robert Wray
Faculty of Science, Medicine and Health - Papers: part A
Saturn’s giant moon Titan has a landscape made of organic molecules, which is exposed to hydrocarbon-based rains, rivers, and lakes. Many of Titan’s surface features could have resulted from dissolution, transport, and evaporite-formation of solid organic materials in a manner similar to dissolution/evaporation processes on Earth. We have constructed an experimental apparatus using a fiber optic UV probe able to determine the rate of dissolution and the amount of material dissolved in hydrocarbon fluids at Titan’s surface temperature of 94 K. For our initial work, benzene was selected as our proxy Titan organic molecule – there is spectral evidence that …
Accuracy Of Micrometeorological Techniques For Detecting A Change In Methane Emissions From A Herd Of Cattle, Johannes Laubach, Mei Bai, Cesar S. Pinares-Patino, Frances A. Phillips, Travis A. Naylor, German Molano, Edgar A. Cardenas Rocha, David W. T Griffith
Accuracy Of Micrometeorological Techniques For Detecting A Change In Methane Emissions From A Herd Of Cattle, Johannes Laubach, Mei Bai, Cesar S. Pinares-Patino, Frances A. Phillips, Travis A. Naylor, German Molano, Edgar A. Cardenas Rocha, David W. T Griffith
Faculty of Science, Medicine and Health - Papers: part A
Micrometeorological techniques are effective in measuring methane (CH4) emission rates at the herd scale, but their suitability as verification tools for emissions mitigation depends on the uncertainty with which they can detect a treatment difference. An experiment was designed to test for a range of techniques whether they could detect a change in weekly mean emission rate from a herd of cattle, in response to a controlled change in feed supply. The cattle were kept in an enclosure and fed pasture baleage, of amounts increasing from one week to the next. Methane emission rates were measured at the herd scale …
Post-Glacial Sea-Level Changes Around The Australian Margin: A Review, Stephen E. Lewis, Craig R. Sloss, Colin V. Murray-Wallace, Colin D. Woodroffe, Scott G. Smithers
Post-Glacial Sea-Level Changes Around The Australian Margin: A Review, Stephen E. Lewis, Craig R. Sloss, Colin V. Murray-Wallace, Colin D. Woodroffe, Scott G. Smithers
Faculty of Science, Medicine and Health - Papers: part A
It has been known since Rhodes Fairbridge's first attempt to establish a global pattern of Holocene sea-level change by combining evidence from Western Australia and from sites in the northern hemisphere that the details of sea-level history since the Last Glacial Maximum vary considerably across the globe. The Australian region is relatively stable tectonically and is situated in the 'far-field' of former ice sheets. It therefore preserves important records of post-glacial sea levels that are less complicated by neotectonics or glacio-isostatic adjustments. Accordingly, the relative sea-level record of this region is dominantly one of glacio-eustatic (ice equivalent) sea-level changes. The …
The Use Of Remote Sensing To Scale Up Measures Of Carbonate Production On Reef Systems: A Comparison Of Hydrochemical And Census-Based Estimation Methods, Sarah Hamylton, Jacob Silverman, Emily Shaw
The Use Of Remote Sensing To Scale Up Measures Of Carbonate Production On Reef Systems: A Comparison Of Hydrochemical And Census-Based Estimation Methods, Sarah Hamylton, Jacob Silverman, Emily Shaw
Faculty of Science, Medicine and Health - Papers: part A
The present study uses remote-sensing imagery to estimate carbonate production of the complete One Tree Island reef system, Great Barrier Reef, using hydrochemical (alkalinity reduction) and census-based (budgetary) methods. For five sites representing different benthic cover types across the reef system, carbonate production is determined using hydrochemical techniques that incubate substrates in a local aquarium and measure total alkalinity, total ammonia nitrogen, and total oxidized nitrogen. Local estimates are scaled up to the reef-system scale using a WorldView-2 satellite image, which is ground truthed against a field data set of 350 spatially referenced records of benthic assemblage. Annual total reef …
Product Branching Fractions Of The Ch + Propene Reaction From Synchrotron Photoionization Mass Spectrometry, Adam J. Trevitt, Matthew B. Prendergast, Fabien Goulay, John D. Savee, David L. Osborn, Craig A. Taatjes, Stephen R. Leone
Product Branching Fractions Of The Ch + Propene Reaction From Synchrotron Photoionization Mass Spectrometry, Adam J. Trevitt, Matthew B. Prendergast, Fabien Goulay, John D. Savee, David L. Osborn, Craig A. Taatjes, Stephen R. Leone
Faculty of Science, Medicine and Health - Papers: part A
The CH(X2Π) + propene reaction is studied in the gas phase at 298 K and 4 Torr (533.3 Pa) using VUV synchrotron photoionization mass spectrometry. The dominant product channel is the formation of C4H6 (m/z 54) + H. By fitting experimental photoionization spectra to measured spectra of known C4H6 isomers, the following relative branching fractions are obtained: 1,3-butadiene (0.63 ± 0.13), 1,2-butadiene (0.25 ± 0.05), and 1-butyne (0.12 ± 0.03) with no detectable contribution from 2-butyne. The CD + propene reaction is also studied and two product channels are observed that correspond to C4H6 (m/z 54) + D and C4H5D …